JP3089185B2 - Magnetic recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head type magnetic recording / reproducing apparatus which converts a video signal or an audio signal into digital data and records and reproduces the data on a magnetic tape, and particularly, accurately detects the current position of the magnetic tape. The present invention relates to a magnetic recording / reproducing apparatus capable of performing the above.

[0002]

2. Description of the Related Art Conventionally, various methods have been proposed for detecting the current position of a magnetic tape when the magnetic tape is fast-forwarded or rewinded at a high speed. For example, a method of detecting by measuring the thickness of a magnetic tape wound on a reel optically, a method of detecting by a rotation ratio of a supply reel and a take-up reel, a detection using a linear track on a magnetic tape And a method of detecting information by reading information written on a track on a magnetic tape by a rotating head has been proposed.

In the method of detecting the current position of the magnetic tape by reading the information of the track number written in a part of the track on the magnetic tape, the magnetic tape is rotated at the time of fast-forward or rewind. It is necessary to run at high speed while being wound around.

FIG. 7 shows a track pattern on the magnetic tape MT. In digital magnetic recording / reproducing devices,
One frame of a video signal is divided into ten tracks and recorded, and an area TRN for writing a track number is set in a partial area of each track TR. In the figure,
A chain line LA indicates a head trace during recording / reproduction, a chain line LB indicates a head trace during rewinding, and a chain line LC indicates a head trace during fast-forwarding. FIG. 8 shows an envelope waveform of a signal read by the rotary head during high-speed running of the tape. (A) shows the envelope waveform in the rewind mode, and (b) shows the envelope waveform in the fast-forward mode.

[0005]

When fast-forwarding or rewinding is performed while the magnetic tape is wound on a rotating drum, the take-up reel is driven against the load of a guide post or tension post for guiding the magnetic tape. Therefore, extra power consumption is required, which hinders speeding up the tape feeding.

In addition, during high-speed running, fluctuations in the load on the guide post deteriorate contact between the magnetic tape and the rotary head, making it difficult to read a track number stably. Therefore, a direct drive system in which the reel is directly driven by a motor is conceivable, but the cost is greatly increased.
As a countermeasure, it is preferable to perform fast-forward or rewind without winding the magnetic tape around the rotating drum. However, in this case, since the track number written on the magnetic tape cannot be read, the current position of the magnetic tape cannot be detected.

Therefore, there has been proposed an apparatus that measures the rotation cycle of the reel, calculates the current position of the magnetic tape and the integrated rotation number of the reel from the measurement result, and controls the position of the magnetic tape (for example, Japanese Patent Application Laid-Open No. H11-157572). See Japanese Unexamined Patent Publication No. Hei. However, even with this apparatus, the current position of the magnetic tape and the integrated rotation speed of the reel cannot be accurately detected due to variations in the diameter of the reel hub or uneven winding of the magnetic tape.

An object of the present invention is to provide a magnetic recording / reproducing apparatus capable of accurately detecting the position of a magnetic tape even when fast-forwarding or rewinding at a high speed without winding the magnetic tape around a rotating drum. It is in.

[0009]

According to a first aspect of the present invention, there is provided a magnetic recording / reproducing apparatus, comprising: a loading mechanism for mounting a magnetic tape in a cassette case loaded therein to a rotating drum in a contact or non-contact state; A tape drive mechanism for driving the tape to travel between a pair of reels, a mechanism body having a reel rotation speed detecting means for outputting a signal corresponding to the rotation speed of the reel, and a driving mechanism for controlling the loading mechanism and the tape travel mechanism to rotate the reel. A control circuit for calculating the total number of rotations of the reel from the output of the number detection means, and controlling the recording and reproduction of data including a video signal and a track number on the magnetic tape; and the total rotation of the reel when recording and reproducing data on the magnetic tape. And a memory circuit for storing the track number and the track number. Read from the integrated rotation number of the memory circuit of the reel corresponding to, as compared with the cumulative rotational speed of the magnetic tape reel traveling at a non-contact state to the rotating drum, and is configured to perform positioning of the magnetic tape.

In the magnetic recording / reproducing apparatus according to a second aspect of the present invention, the memory circuit according to the first aspect stores the accumulated number of rotations of the reels and the track number at an arbitrary sampling interval, and the control circuit executes Means are provided for interpolating the accumulated number of rotations of the reels and the track number during the missing period.

In a magnetic recording / reproducing apparatus according to a third aspect of the present invention, the interpolating means according to the second aspect is such that a track pitch P in a tape feed direction, a tape thickness t, and an outer diameter D ₀ of a reel hub are provided.
K1 = π / P × t k2 = π / P × D ₀ Coefficients k1 and k2 of at least two sets of sampled reels n _p before and after one sampling period, tape tracks as numbers n _p, and means for calculating the coefficients k1, k2 from ^{_{n p = k1 × n p 2}} + k2 × n p, based on the coefficients k1, k2 that this _{calculation, n q = k1 × n q} 2 + k2 × n _q cumulative revolution speed of the reel of the missing period by sampling the n _q, and means for calculating a track number n _q of the tape.

In a magnetic recording / reproducing apparatus according to a fourth aspect of the present invention, the interpolating means according to the second aspect is such that the track pitch P in the tape feed direction, the tape thickness t, and the outer diameter D ₀ of the hub of the reel.
K1 = π / P × t k2 = π / P × D ₀ Coefficients k1 and k2 of the integrated reel rotation speed n _p stored in the memory circuit and the tape track number N _{p in} the series of information based on the accumulated number of revolutions of any of a number of track number and the reel, means for calculating the coefficients k1, k2 using ^{_{n R = k1 × n R 2}} + k2 × n R, the coefficients k1, k2 that this calculated when the coefficient k1, k2 cumulative revolution speed of the other track number and the reel was not used to calculate the is represented by ^{_{n S = k1 × n S 2}} + k2 × n S , the mechanism body the magnetic tape Out of the series of track numbers and the total number of revolutions of the reels stored in the memory circuit, except for the track number and the total number of rotations of the reel in the state at the time of the tape removal, and delete the other numbers. k And means for recording the k2.

According to a fifth aspect of the present invention, there is provided the magnetic recording / reproducing apparatus according to the first aspect, wherein the track number and the integrated rotation number of the reel are recorded on a magnetic tape area.
When rotating in both forward and reverse directions, the track number determined by the total number of rotations of the reel on the winding side and the total number of rotations of the reel on the sending side or the track number recorded on the magnetic tape is sampled in a storage device other than the magnetic tape. Means for recording information.

The magnetic recording / reproducing apparatus according to a sixth aspect of the present invention is a magnetic recording / reproducing apparatus according to the fourth aspect, wherein a track number, a total number of reel rotations, and coefficients k1 and k2 in a state at the time of taking out the magnetic tape are set on an optional magnetic tape.・ Provide means for recording on a track.

[0015]

In the magnetic recording / reproducing apparatus according to the present invention, even when a fast-forward or rewind operation is performed in a state where the magnetic tape is not in contact with the rotating drum, the accumulated number of rotations of the reel and the track number of the magnetic tape are not changed. Is stored in the memory circuit in a sampling manner, so that this information is reproduced,
By comparing the information on the accumulated rotation number of the reproduced reel corresponding to the target track number to be positioned with the accumulated rotation number of the reel measured when performing the positioning operation of the magnetic tape, Can be accurately positioned.

[0016]

FIG. 1 is a block diagram showing an embodiment of a magnetic recording / reproducing apparatus according to the present invention, showing a rotary head type digital VTR (video tape recorder). The present embodiment includes a mechanism main body 1 for housing a cassette case, and a control circuit 2 for controlling the mechanism main body 1. The mechanism main body 1 includes a loading mechanism for mounting the magnetic tape MT in the cassette case 11 loaded therein to the rotating drum 12 and the like, and a tape feeding mechanism for feeding the magnetic tape MT.

The loading mechanism is controlled by a loading mechanism driving circuit 3, and the tape feeding mechanism is controlled by a feeding mechanism driving circuit 4. The loading mechanism drive circuit 3 and the transport mechanism drive circuit 4 are controlled by the control circuit 2.

The writing of digital data on the magnetic tape MT or the reading of digital data recorded on the magnetic tape MT is performed by a rotary head 13 mounted on a rotary drum 12. As described above, the digital data recorded on the magnetic tape MT is composed of 10 tracks of the magnetic tape MT as one frame, and each track contains a video signal, an audio signal, and information on the track number of each track. Recorded as data.

Further, frequency generators FG1 and FG2 for generating pulse signals having a frequency corresponding to the number of rotations of each of the reels R1 and R2 are provided near the respective rotating shafts of the pair of reels R1 and R2 of the cassette case 11. is set up. The pulse signals generated from the frequency generators FG1 and FG2 are supplied to the control circuit 2. The control circuit 2 counts this pulse signal and calculates the integrated rotation speed of the reels R1 and R2. In this case, as shown in FIG. 2, it is possible to select between a precision count in which the output pulse signal of the frequency generator FG1 (FG2) is directly input to the counter and a normal count in which the frequency is divided by the frequency divider and then input to the counter. it can. The reel R1 is a supply reel, and the reel R2 is a take-up reel.

The control circuit 2 is connected to a memory circuit 5. As will be described later, the memory circuit 5 stores a track number to be recorded on each track of the magnetic tape MT, and information on the integrated rotation number of the reel.

Next, the operation of this embodiment will be described.
First, an operation for recording a video signal and the like from the winding start position (A point) of the unrecorded magnetic tape MT over the entire area will be described with reference to the flowchart shown in FIG. This operation is started by loading the cassette case 11 into the mechanism main body 1 and setting the apparatus to the recording mode.

First, the loading mechanism drive circuit 3 drives the loading mechanism in the mechanism body 1 to pull out the magnetic tape MT from the cassette case 11 and wind it around the rotating drum 12 in a contact state (step S11).

Next, the running mechanism in the mechanism main body 1 is controlled to be activated by the running mechanism drive circuit 4, and the magnetic tape MT is run from the supply reel R1 to the take-up reel R2 via the rotating drum 12 in the recording mode ( Step S1
2). As a result, the video signal, the audio signal, and the digital data representing the track number of each track output from the control circuit 2 are recorded on the magnetic tape MT by the rotary head 13 (step S13).

At the same time, the track number to be recorded on the magnetic tape MT is stored in the memory circuit 5 at an arbitrary sampling cycle (step S14). Further, the number of rotations of the take-up reel R2 is detected by the frequency generator FG2, and a pulse signal having a frequency corresponding to the number of rotations is supplied to the control circuit 2. This pulse signal is counted by a counter in the control circuit 2 and stored in the memory circuit 5 at an arbitrary sampling cycle as an integrated rotation speed of the reel (step S1).
5). The processing of steps S13 to S15 is repeated until the recording mode ends (step S16). When the recording mode ends, the traveling mechanism drive circuit 4 controls the traveling mechanism in the mechanism main body 1 to stop (step S17), and ends the processing.

Next, the recording of the video signal, the audio signal, and the track number on the magnetic tape MT is completed, and the storage of the track number and the total number of reel rotations in the memory circuit 5 is completed. Cassette case 1
The operation of rewinding within the recorded range without moving 1 and moving it to the designated position will be described with reference to the flowchart shown in FIG.

First, a position where the magnetic tape MT is to be moved is designated (step S21). Next, the information on the track number and the integrated rotation number of the reels stored in the memory circuit 5 is read (step S22), and it is determined whether or not the information on the track number and the integrated rotation number of the reel corresponding to the moving position is stored. (Step S
23).

If it is not stored, interpolation is performed according to the following procedure (step S24). This is because the information on the track number and the integrated rotation speed of the reels stored in the memory circuit 5 is stored for each arbitrary sampling period as described above. This is because interpolation is necessary when information on the data is missing due to sampling.

[0028] Here, the track number N, the cumulative revolution count of the reel n, the track pitch P in the tape feed direction, the tape thickness t, the outer diameter of the hub of the reel as _{D 0, k1 = π / P} × Coefficients k1 and k2 satisfying t k2 = π / P × D ₀ .

First, the coefficients k1 and k2 are calculated from the integrated rotation speed n _p of at least two sets of sampled reels before and after one sampling period and the track number N _{p of the} tape using the following relational expression. Ask. N _p = k1 × n _p ² + k2 × n _p

[0030] Then, based on the coefficients k1, k2 that this calculation, the accumulated rotational speed n _q of the reel in the period in which missing by sampling from the following equation, the tape of the track number N
Calculate _q . N _q = k1 × n _q ² + k2 × n _q

The information on the track number corresponding to the moving position and the integrated rotation number of the reel thus obtained is used if the information is missing by sampling, and the information read out in step S22 is used if the information is sampled. , Respectively, as information on the movement position (step S25).

Next, the loading mechanism in the mechanism body 1 is controlled by the loading mechanism drive circuit 3 to set the magnetic tape MT in a non-contact state in which the magnetic tape MT does not touch the rotating drum 12 (step S26). Next, the running mechanism drive circuit 4 starts and controls the tape running mechanism in the mechanism main body 1 to instruct high-speed rewind running of the magnetic tape MT from the take-up reel R2 to the supply reel R1 (step S27).

Next, the integrated rotation speed of the rotating reel is detected (step S28), and this integrated rotation speed is compared with the integrated rotation speed of the reel corresponding to the track number of the moving position determined in step S25. (Step S29),
Steps S28 to S29 are repeated until they match. If they match, the traveling mechanism drive circuit 4 stops the traveling mechanism in the mechanism body 1 (step S30), and ends the processing. Thus, the positioning of the magnetic tape can be performed.

Next, referring to the flowcharts shown in FIGS. 5 and 6, when the cassette case 11 is once taken out of the mechanism main body 1 and loaded in the mechanism main body 1 again to set an arbitrary mode, the memory circuit 5 A procedure for storing information on the track number and the accumulated number of revolutions of the reel will be described. As an arbitrary mode to be set, there are a recording mode, a reproduction mode, a fast forward mode, a rewind mode, and the like.

First, the loading mechanism drive circuit 3 controls the loading mechanism in the mechanism body 1 to pull out the magnetic tape MT from the cassette case 11 and mount it on the rotating drum 12 in a contact state (step S31). Next, the rotating drum 12 is rotated, and the track number recorded on the magnetic tape MT is read by the magnetic head 13 (step S32).

Next, the track number stored in the memory circuit 5 is read (step S33), and the track number is compared with the track number read from the magnetic tape MT to determine whether the current position of the magnetic tape MT is an unrecorded area. ,
It is detected whether it is a boundary between an unrecorded area and a recorded area or a recorded area (step S34). In the following description, it is assumed that the winding start position of the magnetic tape MT is point A, the winding end position is point C, the point A to the middle point B is a recording area, and the point B to the point C is an unrecorded area. .

If the result of determination in step S34 is that the current position of the magnetic tape MT is in an unrecorded area (points B to C), the traveling mechanism drive circuit 4 controls the traveling mechanism in the mechanism main body 1 to control the magnetism. In a state where the tape MT is in contact with the rotary drum 12, the mode is set to the rewind mode, and a command to start running is issued (step S35).

Thus, the magnetic tape MT is rewound from the take-up reel R2 toward the supply reel R1. When the position of the magnetic tape MT comes to the boundary position (point B) between the unrecorded area and the recorded area (step S36), the track number recorded on the magnetic tape MT becomes
3 and the track number information is sampled and recorded in the memory circuit 5 (step S37).
At the same time, the integrated rotation speed of the supply reel R1, that is, the integrated rotation speed of the reel obtained by counting the pulse signal of the frequency generator FG1, is sampled and recorded in the memory circuit 5 as information on the supply reel R1 side (step S3).
8). It is assumed that the counter for counting the total number of revolutions has been reset.

This series of processing (steps S37 to S3)
8) up to the winding start position (point A) of the magnetic tape MT (step S39). When the position of the magnetic tape MT comes to the point A, or when the magnetic tape MT comes to the point A without detecting the point B in step S36 (step S4).
0), the traveling mechanism drive circuit 4 controls the tape traveling mechanism in the mechanism main body 1 to perform a forward mode such as recording, reproducing, fast-forwarding in the tape head contact state, or fast-forwarding in the tape head non-contact state. Switch (step S4)
1).

Then, the reset take-up reel R
2 and the track number determined by the track number on the magnetic tape MT or the cumulative number of revolutions of the supply reel R1 or the track number of the recording signal is selected in a mode, and the reel R2 is taken up by the memory circuit 5. (Step S)
42).

At the same time, in the rewind mode, step S3
The supply-side track number and the information on the accumulated number of rotations of the reels stored in 7 to S38 are sequentially cleared from the memory circuit 5 (step S43). This series of processing (steps S42 to S43) is performed until the point B is achieved (step S44). When the point B is reached, the traveling mechanism drive circuit 4 controls the stop of the traveling mechanism in the mechanism main body 1 (step S45). The process ends.

Thus, the position of the area from the point A to the point B on the magnetic tape MT is stored in the memory circuit 5 as the information of the rotation speed of the pair of reels. If the magnetic tape MT is moved again in this area, the counting error due to reel winding unevenness or the like can be removed by counting again the accumulated number of rotations of the reel.

Next, at step S34, the current position of the magnetic tape MT is set to the boundary between the unrecorded area and the recorded area (point B).
If it is determined that the track number on the magnetic tape MT is the same as the track number stored in the memory circuit 5 (step S51). If they match, it is next determined whether the feed direction of the magnetic tape MT is the forward mode (step S52).

If the feed direction of the magnetic tape MT is the forward direction mode, the recording mode is for recording in an unrecorded area, and the traveling mechanism drive circuit 4 controls the traveling mechanism in the mechanism body 1 to set the recording mode ( Step S53), magnetic tape M
The track number to be recorded in T is simultaneously stored in the memory circuit 5 in a sampling manner (step S54), and the integrated rotation speed obtained by counting the pulse signals from the frequency generator FG2 on the take-up reel R2 is stored in the memory circuit 5. It is stored in a sampling manner (step S55). The recording of the processing of steps S54 to S55 ends (step S56).
When the recording is completed, the traveling mechanism drive circuit 4 controls the tape traveling mechanism in the mechanism body 1 to stop (step S).
45), end the process.

If the feeding direction of the magnetic tape MT is the reverse direction (step S52), the running mechanism drive circuit 4 controls the running mechanism in the mechanism main body 1 to set the tape head in the contact mode or the non-contact mode in the rewind mode. Set (Step S5
7). Then, the accumulated number of revolutions of the supply reel R1 is sampled and stored in the memory circuit 5 (step S58), and the track number on the magnetic tape MT is in the tape head contact state, and is taken up in the tape head non-contact state. The track numbers obtained from the integrated rotation speed of the reel R2 are stored in the memory circuit 5 in a sampling manner (step S59). At the same time, the information of the track number on the take-up reel R2 side and the information on the total number of revolutions of the reel is sequentially deleted from the storage device 5 (step S60).

This series of processing (steps S58 to S6)
0) until the start of winding of the magnetic tape MT (point A). At the point A (step S61), the traveling mechanism drive circuit 4 controls the traveling mechanism in the mechanism body 1 to switch to the forward mode (step S41), and step S42.
Execute the following processing.

If it is determined in step S51 that the track number on the magnetic tape MT is different from the track number in the memory circuit 5, the traveling mechanism drive circuit 4 causes the mechanism body 1
The tape running mechanism is controlled to enter a rewind mode in a tape head contact state (step S62). After that, the processing after step S37 is executed.

Next, when it is determined in step S34 that the current position of the magnetic tape MT is in the recording area,
If the magnetic tape M is determined to be between
It is determined whether the track number on T matches the track number stored in the memory circuit 5 (step S).
71). If they match, it is determined whether the feed direction of the magnetic tape MT is in the forward mode (step S72).

If the feed direction of the magnetic tape MT is the forward direction mode, the processing after step S41 is executed, and if it is the reverse direction, the processing after step S57 is executed. If it is determined in step S71 that the track number on the magnetic tape MT is shifted from the track number in the memory circuit 5, the processing from step S62 is executed.

By the way, if the track number is N, the track pitch in the tape running direction is P, the tape thickness is t, the accumulated number of rotations of the reel is n, and the outer diameter of the hub of the reel is D ₀ , N = π / P × t × n ² + π / P × D ₀ × n. Generally, the track pitch, tape thickness, and reel hub diameter are different for each cassette, and treating them as constants in advance saves memory, but degrades the positioning accuracy of the tape.

Therefore, assuming that k1 = π / P × t k2 = π / P × D ₀ , the coefficient k1, k2 is calculated using the least squares method or the like based on the values of some track numbers and the integrated rotation speed of the reel. The value of k2 is calculated, and the track number and the value of the integrated rotation number of the reel are compared with each other. If the value is within a certain allowable range, the information on the positional relationship of the tape at the time of tape removal and the track The information of the starting point position and the information of the ending point position of the area in which the information of the relationship between the number and the integrated rotation number of the reel is obtained, the track number and the reel stored in the memory circuit 5 except for the values of the coefficients k1 and k2. , The information on the accumulated number of revolutions can be deleted, and the area of the memory circuit 5 can be saved.

Here, if the outer diameter D ₀ of the reel hub is an arbitrary reel diameter on the winding side in the reverse direction in the relational expression of the track number N and the cumulative number of rotations n of the reel, the winding side in the reverse direction on the feeding side Can be handled by the same equation, and by treating the coefficients k1 and k2 separately for both of the pair of reels, the relationship between a series of track numbers and the integrated rotation number of the reels can be accurately grasped.

If a series of track numbers and the total number of rotations of the reel cannot be related by a set of coefficients k1 and k2 due to unevenness in the thickness and winding of the tape, the coefficients k1 and k2 should be set to appropriate values. By dealing with a plurality of sections, the relationship between the track number and the total number of rotations of the reels can be accurately grasped.

Further, by enabling the sampling interval between the track number and the integrated rotation number of the reel to be set arbitrarily, the storage capacity of the memory circuit can be saved. Is unnecessary, and the area of the memory circuit can be saved.

If the track number at the time of taking out the magnetic tape, the information of the accumulated number of rotations of the reels, and the coefficients k1 and k2 are recorded on the optional tracks on the tape, the function of reproducing the optional tracks is provided. In the mechanism body marked with, the storage capacity of the memory circuit can be further reduced.

[0056]

According to the present invention, in the high-speed fast-forward or rewind mode, the magnetic tape does not come into contact with the rotating drum, so that an increase in the load on the guide post and a fluctuation in the load can be suppressed. Error factors in controlling the position of the magnetic tape, such as variations in reel diameter, tape winding unevenness, and tape thickness unevenness, by ascertaining the track number of the magnetic tape from the accumulated number of reel rotations obtained from the frequency generator. Can be eliminated, and the positioning of the magnetic tape can be performed accurately.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a magnetic recording / reproducing apparatus according to the present invention.

FIG. 2 is a block diagram showing switching between a precision count for directly inputting an output pulse signal of a frequency generator to a counter and a normal count for inputting to a counter after frequency division by a frequency dividing circuit.

FIG. 3 is a flowchart for explaining an operation when recording a video signal or the like from a winding start position of an unrecorded magnetic tape over the entire area.

FIG. 4 is a flowchart illustrating an operation when rewinding is performed within a recorded range after the operation illustrated in FIG. 3 is completed.

FIG. 5 is a flowchart illustrating an operation when the cassette case is removed from the mechanism main body and is loaded again into the mechanism main body.

FIG. 6 is a flowchart illustrating an operation when the cassette case is removed from the mechanism main body and is loaded again into the mechanism main body.

FIG. 7 is a diagram showing a relationship between a track pattern of a magnetic tape and a head trace.

8A and 8B are diagrams showing envelope waveforms at the time of high-speed running of the tape. FIG. 8A is a waveform diagram at the time of rewinding, and FIG. 8B is a waveform diagram at the time of fast-forwarding.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 mechanism main body 2 control circuit 3 loading mechanism drive circuit 4 traveling mechanism drive circuit 5 memory circuit 11 cassette case 12 rotating drum 13 rotating head MT magnetic tape R1 supply reel R2 take-up reel FG1, FG2 frequency generator

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 27/10 G11B 15/00

Claims (5)

(57) [Claims] 1. A loading mechanism for mounting a magnetic tape in a cassette case loaded therein to a rotating drum in a contact or non-contact state, a tape traveling mechanism for driving the magnetic tape to travel between a pair of reels, and the reel A mechanism main body having a reel rotation speed detecting means for outputting a signal corresponding to the rotation speed of the reel, a drive control of the loading mechanism and the tape running mechanism, and calculating an integrated rotation speed of the reel from an output of the reel rotation speed detecting means A control circuit for controlling the recording and reproduction of data including a video signal and a track number on the magnetic tape; and a memory circuit for storing the integrated rotation number of the reel and the track number when recording and reproducing data on the magnetic tape. Wherein the control circuit has a track corresponding to a track number of a target position for positioning the magnetic tape. The magnetic tape is read from the memory circuit, and is compared with the integrated rotational speed of the reel of the magnetic tape running in a non-contact state with the rotating drum, so as to perform positioning of the magnetic tape. The storage of the accumulated number of revolutions of the reel and the track number in the memory circuit is performed at an arbitrary sampling interval,
The magnetic recording / reproducing apparatus according to claim 1, wherein the control circuit includes means for interpolating the integrated number of rotations of the reel and the track number during a period in which the sampling is omitted. Wherein said interpolating means, the track pitch P in the tape feed direction, the tape thickness t, as the outer diameter D ₀ of the hub of the reel, k1 = π / P × t k2 = π / P × D 0 becomes coefficient k1 , K2, the cumulative number of rotations n _p of at least two sets of sampled reels before and after one sampling period, the tape track number N _p , the coefficient k1 from N _p = k1 × n _p ² + k2 × n _p , K2; and, based on the calculated coefficients k1 and k2, the integrated rotation speed n _q of the reel during the period missing from the sampling from N _q = k 1 × n _q ² + k ² × n _q , 2. The magnetic recording / reproducing apparatus according to claim 1, further comprising: means for calculating a track number _Nq . Wherein said interpolating means, the track pitch P in the tape feed direction, the tape thickness t, as the outer diameter D ₀ of the hub of the reel, k1 = π / P × t k2 = π / P × D 0 becomes coefficient k1 , K2, the integrated rotation speed n _{R of} the reel stored in the memory circuit,
A series of cumulative number of revolutions of any of a number of track number and the reel of the information of the track number N _R of the tape, means for calculating the coefficients k1, k2 using ^{_{N R = k1 × n R 2}} + k2 × n R When the accumulated rotational speed n _S other track numbers n _S and the reel was not used to calculate the coefficients k1, k2 coefficients k1, k2 that this calculated based _{is, n S = k1 × n S} 2 when + represented by k2 × n _S, wherein upon removal of the magnetic tape from the mechanism body, the memory circuit a series of track numbers and of the cumulative revolution count of the reel stored in the track number and the reel in a state when the tape is taken out 2. The magnetic recording / reproducing apparatus according to claim 1, further comprising: means for erasing other than the accumulated number of revolutions and recording new coefficients k1 and k2. 4. When rotating in both forward and reverse directions in an area of the magnetic tape in which the track number and the integrated rotation speed of the reel are recorded, the integrated rotation speed of the reel on the winding side and the reel on the sending side. 2. A magnetic recording / reproducing apparatus according to claim 1, further comprising means for recording a track number determined by the cumulative number of revolutions of the magnetic tape or the track number recorded on the magnetic tape in a storage device other than the magnetic tape in a sampling manner. apparatus. 5. A track number, a total number of rotations of a reel, and a coefficient k in a state where the magnetic tape is taken out.
4. A magnetic recording / reproducing apparatus according to claim 3, further comprising means for recording 1, k2 on an optional track on said magnetic tape.